Abstract：
BACKGROUND: Bangladesh introduced the 10-valent pneumococcal conjugate vaccine (PCV10) for children aged < 1 year in March 2015. Previous vaccine effectiveness (VE) studies for pneumonia have used invasive pneumococcal disease or chest X-rays. None have used ultrasound. We sought to determine the VE of PCV10 against sonographically-confirmed pneumonia in three subdistrict health complexes in Bangladesh.
METHODS: We conducted a matched case-control study between July 2015 and September 2017 in three subdistricts of Sylhet, Bangladesh. Cases were vaccine-eligible children aged 3-35 months with sonographically-confirmed pneumonia, who were matched with two types of controls by age, sex, week of diagnosis, subdistrict health complex (clinic controls) or distance from subdistrict health complex (community controls) and had an illness unlikely due to Streptococcus pneumoniae (clinic controls) or were healthy (community controls). VE was measured using multivariable conditional logistic regression.
RESULTS: We evaluated 8926 children (average age 13.3 months, 58% boys) with clinical pneumonia by ultrasound; 2470 had pneumonia with consolidations ≥ 1 cm; 1893 pneumonia cases were matched with 4238 clinic controls; and 1832 were matched with 3636 community controls. VE increased with the threshold used for consolidation size on ultrasound: the adjusted VE of ≥ 2 doses vs. non-recipients of PCV10 against pneumonia increased from 15.8% (95% CI 1.6-28.0%) for consolidations ≥ 1 cm to 29.6% (12.8-43.2%) for consolidations ≥ 1.5 cm using clinic controls and from 2.7% (- 14.2-17.2%) to 23.5% (4.4-38.8%) using community controls, respectively.
CONCLUSIONS: PCV10 was effective at reducing sonographically-confirmed pneumonia in children aged 3-35 months of age when compared to unvaccinated children. VE increased with the threshold used for consolidation size on ultrasound in clinic and community controls alike. This study provides evidence that lung ultrasound is a useful alternative to chest X-ray for case-control studies evaluating the effectiveness of vaccines against pneumonia.
METHODS: We conducted a matched case-control study between July 2015 and September 2017 in three subdistricts of Sylhet, Bangladesh. Cases were vaccine-eligible children aged 3-35 months with sonographically-confirmed pneumonia, who were matched with two types of controls by age, sex, week of diagnosis, subdistrict health complex (clinic controls) or distance from subdistrict health complex (community controls) and had an illness unlikely due to Streptococcus pneumoniae (clinic controls) or were healthy (community controls). VE was measured using multivariable conditional logistic regression.
RESULTS: We evaluated 8926 children (average age 13.3 months, 58% boys) with clinical pneumonia by ultrasound; 2470 had pneumonia with consolidations ≥ 1 cm; 1893 pneumonia cases were matched with 4238 clinic controls; and 1832 were matched with 3636 community controls. VE increased with the threshold used for consolidation size on ultrasound: the adjusted VE of ≥ 2 doses vs. non-recipients of PCV10 against pneumonia increased from 15.8% (95% CI 1.6-28.0%) for consolidations ≥ 1 cm to 29.6% (12.8-43.2%) for consolidations ≥ 1.5 cm using clinic controls and from 2.7% (- 14.2-17.2%) to 23.5% (4.4-38.8%) using community controls, respectively.
CONCLUSIONS: PCV10 was effective at reducing sonographically-confirmed pneumonia in children aged 3-35 months of age when compared to unvaccinated children. VE increased with the threshold used for consolidation size on ultrasound in clinic and community controls alike. This study provides evidence that lung ultrasound is a useful alternative to chest X-ray for case-control studies evaluating the effectiveness of vaccines against pneumonia.
摘要：
背景：孟加拉国于2015年3月为1岁以下儿童推出了10价肺炎球菌结合疫苗（PCV10）。先前针对肺炎的疫苗有效性（VE）研究已使用侵袭性肺炎球菌疾病或胸部X射线。没有人使用超声波。我们试图在孟加拉国的三个分区卫生院中确定PCV10对超声证实的肺炎的VE。
方法：我们于2015年7月至2017年9月在Sylhet的三个分区进行了匹配的病例对照研究。孟加拉国。病例为3-35个月患有超声确诊肺炎的合格疫苗儿童，根据年龄与两种类型的对照相匹配，性别,一周的诊断，分区健康综合体（诊所控制）或与分区健康综合体（社区控制）的距离，并且不太可能因肺炎链球菌而患病（诊所控制）或健康（社区控制）。使用多变量条件逻辑回归测量VE。
结果：我们评估了8926名儿童（平均年龄13.3个月，58％的男孩）通过超声检查患有临床肺炎；2470例合并≥1cm的肺炎；1893例肺炎病例与4238例临床对照相匹配；1832例与3636例社区对照相匹配。VE随用于超声巩固大小的阈值而增加：≥2剂量的调整VE与非PCV10治疗肺炎的接受者从≥1厘米合并的15.8%(95%CI1.6-28.0%)增加到≥1.5厘米合并的29.6%(12.8-43.2%)，使用社区控制的患者从2.7%(-14.2-17.2%)增加到23.5%(4.4-38.8%)，分别。
结论：与未接种疫苗的儿童相比，PCV10可有效减少3-35个月儿童的超声确诊肺炎。VE随临床和社区对照中超声巩固大小的阈值而增加。这项研究提供了证据，表明肺部超声是胸部X射线的有用替代方法，用于评估疫苗对肺炎的有效性的病例对照研究。
方法：我们于2015年7月至2017年9月在Sylhet的三个分区进行了匹配的病例对照研究。孟加拉国。病例为3-35个月患有超声确诊肺炎的合格疫苗儿童，根据年龄与两种类型的对照相匹配，性别,一周的诊断，分区健康综合体（诊所控制）或与分区健康综合体（社区控制）的距离，并且不太可能因肺炎链球菌而患病（诊所控制）或健康（社区控制）。使用多变量条件逻辑回归测量VE。
结果：我们评估了8926名儿童（平均年龄13.3个月，58％的男孩）通过超声检查患有临床肺炎；2470例合并≥1cm的肺炎；1893例肺炎病例与4238例临床对照相匹配；1832例与3636例社区对照相匹配。VE随用于超声巩固大小的阈值而增加：≥2剂量的调整VE与非PCV10治疗肺炎的接受者从≥1厘米合并的15.8%(95%CI1.6-28.0%)增加到≥1.5厘米合并的29.6%(12.8-43.2%)，使用社区控制的患者从2.7%(-14.2-17.2%)增加到23.5%(4.4-38.8%)，分别。
结论：与未接种疫苗的儿童相比，PCV10可有效减少3-35个月儿童的超声确诊肺炎。VE随临床和社区对照中超声巩固大小的阈值而增加。这项研究提供了证据，表明肺部超声是胸部X射线的有用替代方法，用于评估疫苗对肺炎的有效性的病例对照研究。
